Control system for radio receiving sets



March 13, 1934. w ELLMAN ET AL CONTROL SYSTEM FOR RADIO-RECEIVING SETS Original Filed Jan. 21, 1931 Patented Mar. 13, 1934 UITED STATES PATEN Walter Ellman and Fred Berhley, Astoria, N. Y.

Original application January 21, 1931, Serial No.

510,299. Divided and this application September 18, 1931, Serial No. 563,636

2 Claims.

This invention relates to an electrically oper ated phonograph recording device, and controlling apparatus therefor, and this application is a division of our copending application filed January 21, 1931 and bearing the serial number 510,299.

More particularly, the invention relates to a novel electrically operated device for recording sound effects on phonograph cylinders or disks and a controlling apparatus so arranged and constructed that this recording device may be used in connection with a microphone, a radio receiver, and pick-up or electrical reproducer, the apparatus embodying as one element thereof a switch whereby the various devices may be brought into and out of electrical relation.

One important object of the invention is to provide, in combination with an electrical reproducer, an electrical phonograph recorder, aloud speaker, and a microphone transformer; connections between such elements and a three position switch arranged so that in one position a radio instrument may be connected to the recorder so that a program may be recorded, in a second position the microphone transformer may be connected to the recorder so as to have a silent recording, and in a third position the pick-up and recorder may be simultaneously used so that the recording may be heard at the time it is being effected.

A second important object of the invention is to provide a novel controlling device and switch adapted to be used in connection with standard instruments of the character above described.

A third important object of the invention is to provide a novel wiring arrangement for connecting the various instrumentalities used herein.

With the above and other objects in view as will be hereinafter apparent, the invention consists in general of certain novel arrangements of parts and combinations of details hereinafter fully described, illustrated in the accompanying drawing, and specifically claimed.

In the accompanying drawing, like characters of reference indicate like parts in the several views, and:

Figure 1 is a diagrammatic view showing the switch, the various instruments and the wiring connections therebetween.

Figure 2 is a face view of the control box wherein the controlling mechanism for the invention is held.

The recording device used herewith is shown and described in our copending application for patent above noted and it will there be seen that the recording device includes an arm 16.

On the end of the arm 16 is mounted a standard electrical recording device l6 provided with a recording point 16 which, may be of hardened steel or may be made from a sapphire, diamond, or other suitable material. It is of course understood that while recording on metallic plates the point 16* will be preferably made from a diamond. This recording head 16 is preferably of a type resembling a polarized relay, as can be seen by reference to the diagrammatic showing in Figure 1, wherein a pair of opposed electro-magnets 16 operated upon a pivoted armature 16 carrying the recording point 16*.

The apparatus used in connection with the recorder just described, is preferably contained in a-suitable casing such as is shown at C, the view Figure 2 showing the face of this casing. In this casing is mounted a microphone transformer 30, the primary winding of which is connected to a suitable battery 30*. One terminal of the battery 30 is connected by a suitable conductor 30 to a microphone control switch 30, from one terminal of which a movable contact 30 extends to a resistance Bil connected to the other terminal of the battery by conductor 30 this terminal being also grounded as at 30 The other terminal of the switch :30 is connected by a conductor 30* to the middle point or neutral point of the primary winding of the transformer 30. One end of this primary winding is connected by a conductor 30 to one plug connection 31, while the other end is connected to a similar conductor 30 to a second plug connection 31. Between the two plug connections is a third plug connection 31 groundedas at 31'. The plug connections 31 are spaced in the usual manner so as to receive the connections from a microphone (no-t shown) which may be of any standard type. The switch employed herewith includes a casing 37 which is mounted on an insulated base 37, the casing beingpreferably grounded at 37 Supported on this base at one side of the casing are spring contact fingers 38, 39, 40, 41, and 42. On the opposite side of the casing the base 37' supports the spring contact fingers 43, 44, 45, and 46.

At the top of the casing is a contact controlling disk 47, which is rotatably mounted on a shaft 48 and is provided with an upstanding handle 49 by means of which the disk may be oscillated to one position or another, as desired. Each of the contact fingers 42 and 43 is provided at its upper end with an extension 50 adapted to be engaged by an insulated lug 51 fixed on the disk. The contact fingers 42 and 39 on the first side, extend abovethe remaining contact fingers and are connected for simultaneous operation by an insulated bar 52. Similarly on the other side the contact fingers 45 and 43 extend above the remaining contact fingers and are connected for simultaneous operation by insulated bar 53.

As shown in Figure 1 it will be seen that under the position there indicated in full lines, which may be termed the second position of the switch, the contact fingers are disconnected. Now if the switch be swung to the dotted line position, indicated as first position in Figure 1, then the right hand lug 51 will engage the right hand projection 50. This will close the contact finger 43 on the contact finger 44 and the contact finger 45 on the contact finger 46, leaving the contact fingers 39 and 40 in closed position, but leaving the finger 38 free from the finger 39 and the fingers 41 and 42 open. Again, if the switch be swung to third position as indicated in Figure l, the contact between fingers 39 and 46 will be open and the finger 39 will be closed on finger 38 and finger 42 will be closed on finger 41, the right hand fingers being left in open position.

Now, the secondary of the transformer 30 has one end connected by a conductor 54 with the finger 46. The other end of this secondary is connected by a conductor 55 with a jack 56 arranged ior the connection of one of the output leads of a radio receiver, or for the connection of input end of the amplifier. From the conductor 55 leads ground wire 5'7 which extends to the ground through a condenser 58, and also from the conductor 55 leads a conductor 59 which extends to one terminal of the electrically operated pick-up or reproducer 33. The other terminal of this reproducer 33 is connected by conductor 60 with the contact 41. The contacts 42 and 45 are connected in multiple by conductor 61 and from this conductor leads a conductor 62 which extends to one terminal of a resistance 32 traversed by a movable contact 63, this resistance and contact forming a potentiometer. The other terminal of this potentiometer is connected by a conductor 64 to the wire 57. The movable contact 63 is connected by a conductor 65 to the contact 39. The contacts 38 and 40 are connected in multiple by wire 66 and from this multiple connection a conductor 6'7 extends to a jack 63 to which may be connected the remaining lead of the output of the radio receiver or the remaining input terminal of a suitable amplifier (not shown). The contact 43 is grounded as at 69.

Suitable jacks 34 are provided for the connection of the output leads of the amplifier and these jacks are connected in series by conductors '70 to the primary winding '71 of a loud speaker transformer 36, one terminal of which is connected to a conductor '72 with one terminal of voice coil or winding 36' of a loud speaker 35. The other terminal of the secondary 36 is connected by a conductor '73 to one terminal of the windings of the magnets 16, the other terminal. of these windings being connected by a conductor "14 with the remaining terminal of the coil 36'. The conductor 74 is connected by a conductor '75 with the contact 44. The switch arm 49 acts through a suitable slot '76 formed in a switch plate '77 mounted on the casing C, and the microphone switch and its resistance is controlled by a button '73 mounted on said casing, while the potentiometer is controlled by a button '79 similarly mounted.

In the operation of this device, let it be supposed that the switch arm is in the first position,

as shown in Figure 1. In this position it is to be understood that a microphone is connected to the microphone transformer 30 through the plug sockets 31 so that electrical impulses from the microphone will travel through the primary winding of the transformer and thus afiect the secondary winding thereof. It will be remembered also in this position that the contacts 45 and 46 are closed as are the contacts 43 and and contacts 39 and 46. Also, when used in connection with the microphone, the radio receiver will be omitted and the amplifier will be plugged in so the connection will be made between the sockets or jacks 56 and 63 and sockets or jacks 34 through the amplifier. Under these circumstances current will flow from one terminal of the secondary of transformer 36 through conductor 54, contact 46, contact 45, conductor 61, conductor 62, potentiometer 32, conductor 64, jack 56, primary '71, and the amplifier. This will affect the primary winding '71 which will in turn afiect the secondary of the transformer 36 so that current will now fiow from one terminal of the transformer 36 through the conductor '73, re-

if the reproducer 33 be out of service the recording will be silent.

Now assuming the switch to be in the second position. In this position the only contacts which are closed are the contacts 39 and 40.

Under these conditions the microphone is disconnected and the radio receiver is connected to the jacks 56 and 68 so that the current will fiow from the jack 56 through conductor 64, potentiometer 32, conductor 65, contact 39, contact 40, conductor 6'7, and jack 68 back to the receiver. The amplifier, being still connected, the primary winding '71 will again be affected by the current impulses from the radio receiver, but in this case, the contact 44 being open, current will fiow from one terminal of the transformer 36 through conductor 72, horn winding 36', conductor '74, recorder 16 and conductor '73 to the other terminal of '76. Under these conditions, the radio program received by this instrument will be heard from the horn 35 and at the same time the recorder will operate to record such program on a suitable disk on the platen '7.

Assuming now the third position of the switch, the contacts 38 and 39 will be closed, as will also be the contacts 41 and 42. Under these circumstances-phonograph pick-up 33 will come into play, the action being as follows:

From one terminal of this pick-up current will flow through the conductor 59, conductor 55, and conductor 64 to the jack 56, while from the other terminal of the pick-up current will fiow through conductor 60, contact 41, contact 42, conductor 61, conductor 62, potentiometer 32, conductor 65, contact 39, contact 38, conductor 67 to the jack 68. Again, this wfll affect the primary winding 31 and as before, current will flow through the closed circuit embodying the horn winding 36' and the recorder 16 thus recording the phonographic record operating the pick-up 33. Un-

der these circumstances it is to be understood that this pick-up 33 is located on a phonograph other than that employing the recording instrument.

There has thus been provided a highly efficient device of the kind described and for the purpose specified.

It is obvious that many minor changes may be made in the form and construction of the apparatus without departing from the material principles involved and it is not therefore desired to confine the invention to the exact form herein shown and described, but it is wished to include all. such as properly come within the scope of the invention claimed.

What is claimed, is:

1. In apparatus of the kind described, an electrical reproducer for phonograph records, an electrical phonograph recorder, a loud speaker, a microphone transformer and means for connecting a microphone thereto, circuit connections between the reproducer, recorder, loud speaker and transformer and including means to connect the radio receiver apparatus in certain of said connections, and a three position-switch in said connections for controlling the same and connecting the microphone transformer and recorder alone in one position, the radio receiver and recorder with the loud speaker in a second position, and the phonograph connections and recorder alone in a third position, said circuit connections being further arranged for the connection of an amplifier between the radio receiver connections and the loud speaker said loud speaker including a loud speaker transformer horn winding, and having the reproducer connected in a closed circuit, said switch being arranged in its second position to short the circuit to include only the transformer and recorder and being further arranged in its third position to cause inclusion of the horn winding in the circuit.

2. In apparatus of the kind described, an electrical reproducer for phonograph records, an electrical phonograph recorder, a loud speaker, a microphone transformer and means for connecting a microphone thereto, circuit connections between the reproducer, recorder, loud speaker and transformer and including means to connect the radio receiver apparatus in certain of said connections, and a three position switch in said conections for controlling the same and connecting the microphone transformer and recorder alone in one position, the radio receiver and recorder with the loud speaker in a second position, and the phonograph connections and recorder alone in a third position, said loud speaker including a loud speaker transformer horn winding, and having the reproducer connected in a closed circuit, said switch being arranged in its second position to short the circuit to include only the transformer and recorder and being further arranged in its third position to cause inclusion of the horn winding in the circuit.

WALTER ELLMAN. FRED BERHLEY. 

